312 
PROCESS 
STAGES 
DOMAIN 
GEOMETRIC 
SEMANTIC 
Prepare 
and 
Interpret 
Prepare all control data 
Prepare control points 
Prepare a priori SI 
(ground truth) 
Prepare (preprocess) 
inages 
Interpret images, 
encode SI items 
Measure 
and 
transform 
Measure control points 
Compute orientation 
Measure/digitize Si-item 
Transform: 
image —» map—»-ground 
Open file, 
Enter SI item code 
♦ 
Postprocess 
Edit geometry, 
Assess geometric quality, 
(Generalize geometry) 
Edit SI items, 
Assess SI quality, 
(Generalize SI) 
Prepare 
and 
plot 
or 
display 
Prepare control data 
for positioning 
Plot (or display) geometry 
Prepare control data 
for representation 
of SI 
Plot (or display) SI 
Fig. 6: Lay-out of the main procedures and their links 
A procedure can be implemented manually, automatically or combined. 
Manual realization is according to a predetermined sequence of 
operational steps. Automatic realization can be controlled by a 
computer program. 
In the geometric domain, similar procedures are used in analytical 
and digital systems. Differences concern the procedures for handling 
digital images that are inherent in digital systems.